Field of Invention
The present invention relates to a semiconductor device and a method of manufacturing the same. More specifically, the present invention relates to a three-dimensional semiconductor device and a method of fabricating the same.
Description of Related Art
Nonvolatile memory devices are memory devices in which data stored therein is maintained even when its power supply is interrupted. Since the integration of two-dimensional nonvolatile memory devices having memory cells formed in a single layer on a substrate is reaching its physical limit, a three-dimensional nonvolatile memory device in which a plurality of memory cells are vertically stacked on a substrate has been proposed.
The three-dimensional memory device includes alternately stacked interlayer insulating layers and gate electrodes, and channel layers passing through the interlayer insulating layers and gate electrodes. In addition, memory cells and selection transistors may be stacked along the channel layers. Accordingly, to improve operation properties and reliability of the memory device, the selection transistors need to have uniform characteristics.